The present invention relates generally to an apparatus for transferring slices of material in succession between two locations, and, more particularly, to an apparatus for transferring an individual food product slice cut from a supply source to a food product support member such as a backing board or continuous web, without damaging the slice and depositing the same on the support member at a predetermined location.
Various devices are known in the meat production field for the transfer of food material slices, such as bacon slices, onto a support for conveyance to a packaging station. In some of these devices, the transfer of individual, successive slices as they travel from the bacon supply to receiving locations such as a take-off conveyor, a continuous sheet of backing paper or a package backing board is accomplished by way of a mechanical pin or lug which engages or catches successive slices after the slicing knife flings them through the air space separating the material supply and the slice support member.
This method has certain drawbacks, one of which is that the operating speed of the mechanical member is limited because the slice encounters air resistance as it is thrown through the air. The travel of the slice through the air and resultant of placement thereof becomes random, rather than ordered. Additionally, the texture of the product and the temperature of the product after slicing may effect the speed of operation of the transfer apparatus. Exact placement of the product slice onto a support member consequently is not always ensured with a mechanical transfer system of this type because of air resistance and the low mass of the product slice. The operating speed of the entire production line is limited by the maximum operating speed of the transfer member.
Quick transfer of the material slices and exact placement thereof on a support web without altering the size and shape of the slices is desirable to allow the slicing and packaging components of the production line to operate at the most efficient speeds possible. Accurate registration of the individual material slices on the support member is additionally desirable to ensure that the support member is properly loaded. Some attempts at providing material slice transfer mechanisms have utilized rotating drums or cylinders having a vacuum drawn through air passages on the outer surface of the drums to hold material slices in place thereon during the transfer operation. Such mechanisms are described in U.S. Pat. No. 3,978,642, U.S. Pat. No. 4,020,614 and U.S. Pat. No. 4,041,676. Such a mechanism is also described in a related application, Ser. No. 548,171, filed Jul. 5, 1990 now U.S. Pat. No. 5,051,268.
The present invention provides highly efficient and accurate slice registration and, when incorporated into an overall slicing and packaging production line, it can facilitate high-speed transfer of the material slices to a transfer mechanism, thereby enabling the transfer and packaging components to operate at higher speeds commensurate with the component speeds. The present invention sequentially captures individual slices before the slice is completely severed from a supply source onto a substantially flat rotating surface at high speeds matching those of the slicing component without disrupting the slice by stretching or distorting the same. In doing so, the present invention reduces the variables such as meat temperature, slice thickness and meat texture which can commonly affect the meat slicing speed.
In accordance with the present invention, material slices which are sequentially severed from a material supply are transferred by a rotating drum to a support member which can include a take-off conveyor, a continuous support web, or a plurality of sequential individual package support members. The rotating drum is located near to the slicer so that the leading edge of the partially severed slice is forced toward the drum by the slicer and attracted to the drum pneumatically, by way of negative air pressure. This negative air pressure adheres the slice to the outer surface of the drum during the rotation of the drum between the slicing and the desired transfer or deposit locations. When the drum reaches the transfer location, positive air pressure is applied to the slice while the negative air pressure is blocked such that the slice is urged off of the drum onto the adjoining support member. The rotation of the drum can be advantageously synchronized with the cutting action of the slicer to obtain a predetermined spacing between successive material slices. The negative air pressure which adheres individual slices to the rotating drum eliminates the need for a purely mechanical transfer member, while the use of a rotating drum reduces the distance which the slice must travel unrestrained between the slicer and the support member to a minimum.
Accordingly, it is a general object of the present invention to provide an improved apparatus for transferring material slices from a slicing station to support web.
Another object of the present invention is to provide an improved rotating drum for use in a transfer apparatus whereby individual, successive material slices are transferred from a slicing station onto a rotating drum and further onto a support member.
Another object of the present invention is to provide an improved apparatus for depositing material slices on a rotatable support surface which includes a rotating drum operating in conjunction with an inner stationary inner drum, wherein the rotating drum attracts and receives the slice on its outer surface by way of negative air pressure and wherein the outer drum deposits the slice on a support member by way of positive pneumatic pressure supplied to the rotating outer drum by the inner drum.
It is yet a further object of the present invention to provide a transfer apparatus having two operatively associated cylindrical drum members, the first of which being a rotating drum and the second of which being a non-rotating drum, the first drum rotating coaxially around the second, inner non-rotating drum, the inner drum having a first internal pneumatic chamber operatively associated therewith for conveying negative air pressure to the outer surface of the first rotating drum to adhere material slices thereon and a second internal pneumatic chamber operatively associated therewith for conveying positive air pressure to the outer surface of the first drum to urge the material slices off of the first drum, the second drum having a plurality of distinct of first and second passages which respectively communicate air pressure from the first and second pneumatic chambers to the first drum outer surface.
Yet a further object of the present invention is to provide a transfer apparatus having two operatively associated members coaxially aligned, the outer member being capable of rotational movement around the inner member and the inner member being capable of reciprocating movement within the outer member, the outer member having at least one material slice receiving portion thereon which holds material slices in place by negative air pressure.
Another object of the present invention is to provide a transfer apparatus having two rotary drums which adhere material slices to the outer surfaces thereof by negative air pressure.
These and other features and objects of the present invention will become more apparent from a reading of the following detailed description.